Rusty Nail Question # 252.14 (soldering leads to pre-fab track)

[Mark5]

OK, I'm getting close to laying track. On the last "real" layout I had I hand laid all my track and soldered power wires to all rails. Soldering is not a worry when the ties are wood.

Now, being a lazy old man, I decided that the Atlas C55 was good enough for me to pass on hand laying my track on this layout. I got to thinking about that this past weekend, and wondering if a heat sink of sorts will be enough to keep the plastic ties from melting when I solder lead wires on the Atlas C55.

Any experience, tips, or suggestions (preferably experience)?

[tokenbrit]

No recent or N-scale experience, but I never used a heat sink in the (long distant) past, & didn't have problems soldering on the underside of OO/HO track as long as decent iron, solder & flux was used - any minor accidents could be covered with ballast.

I've been told that heat sinks increase the chance of melting something because the heat tends to get drawn away from the solder point by the sink so you actually end up having to apply more heat to the job -> greater risk of melting.

A couple of practice runs on a sacrificial piece of track should help determine if a heat sink helps or hinders. Good luck.

[wm3798]

I usually trim back the first tie or two to make room for the joiner, then do the soldering.  It usually only takes a touch of the soldering pencil to flow it in.  I use thin electronics solder and a bit of flux paste to help it flow.  It works quickly enough that it doesn't affect the plastic.

lee

[3rdrail]

I "tin" both the feeder and the rail and use plenty of flux (the old "Nokorode" variety) and find that the iron is not in contact with the joint long enough to melt the ties.

[Sokramiketes]

OK, I'm getting close to laying track. On the last "real" layout I had I hand laid all my track and soldered power wires to all rails. Soldering is not a worry when the ties are wood.

Now, being a lazy old man, I decided that the Atlas C55 was good enough for me to pass on hand laying my track on this layout. I got to thinking about that this past weekend, and wondering if a heat sink of sorts will be enough to keep the plastic ties from melting when I solder lead wires on the Atlas C55.

Any experience, tips, or suggestions (preferably experience)?

If you really want to be slick about it, solder feeders to the underside of the rail before gluing the track down.  You can cut the tie web apart somewhere in the middle of your piece of flex, then slide the ties out of the way.  Solder the feeder to the bottom of the rail, perpendicular to the direction of the rail (to minimize the width) and slide the ties back on either side of the feeder.  With a compact solder joint, the ties will maintain the proper spacing, and you'll never see the feeder. 

This takes a little extra planning on curve track, but can be done as well.

Otherwise, if you still want to do them from the top, or miss one on the first round and have to go back... use a nice 25W iron.  Some guys swear by a small pencil iron of around 12W, but the smaller irons don't transfer heat as quickly.  The idea is to get in and out as fast as possible, as the longer you're in there, the farther the heat spreads, and the more risk you face melting surrounding ties.  The 25W iron will heat the rail up nice and fast. 

[Mark5]

Thanks a bunch for the input. Will use a piece of flex as a test bed. As I like to have it on the bottom of the rail I'll do like Skibbe says and solder the leads before laying the track when I can.

[bsoplinger]

Thanks a bunch for the input. Will use a piece of flex as a test bed. As I like to have it on the bottom of the rail I'll do like Skibbe says and solder the leads before laying the track when I can.

You'll get the cleanest hardest to see joints that way. A 25W pencil like others have suggested is a great choice for this. Pre-tin the wire at least and you should get nice clean joints that are almost invisible. If you're touching the iron to the rail for more than a few seconds you're doing something wrong. Try using separate flux perhaps.

[Dupesy]

I use a resistance soldering unit, and swear by it for small, intricate work.  It also works great for feeders, and I very rarely deform any ties.  Don't use it on decoder wiring though, as I think I may have fried a few due to the way the soldering unit operates.

[ednadolski]

For a simple & quick heat sink, I cut tiny strips of paper towels and place them on the rail at either side of the joint, then wet them with a drop of water.  This lets me leave the soldering iron in contact with the rail long enough to properly heat the rail to form a good joint.  So long as there isn't any plastic between the solder site and the strip,  you won't melt anything (just don't evaporate away all the water)